1. Field of the Invention
The present invention is directed toward a heated enclosure for a synthetic yarn processing apparatus.
2. Description of the Prior Art
In the processing of synthetic yarn it is well known to enclose heated rolls, such as heated draw rolls, in order to conserve heat and to maintain uniformity of heat transfer along the path of travel of a moving threadline. Representative of such arrangements are those disclosed in U.S. Pat. No. 5,277,858 (Neal), U.S. Pat. 5,259,098 (Gupta), and U. K. Patent 1,023,089 (Allied Chemical Corporation). These arrangements served to enclose the total space occupied by the draw rolls. No particular attention is made to enclose the relatively confined volume through which the yarn travels.
Such arrangements are believed to have thermally efficiencies associated therewith. Large thermal differences are generated when the enclosure is opened. Moreover, since heated air remains enveloped about each individual roll is not conveyed from roll to roll, the yarn experiences relatively large thermal gradients as it is conveyed from roll to roll.
It view of the foregoing it is believed advantageous to provide a more thermally efficient enclosure arrangement that is tailored to correspond to the path of travel of the yarn, as opposed to the members over which the yarn is conveyed, in order to define a pathway for the yarn that maintains the yarn in an environment having a substantially uniform temperature. It is also believed to be advantageous to provide an enclosure arrangement whereby heated gas is conveyed with the yarn as it moves from roll to roll through the apparatus.